Diamonds came into being deep under the earth when the burning magma broke through earth crust and made in it distinctive tubes similar to volcano craters.
These craters (geologists call them burst tubes) are sometimes filled with bluish clay. This bluish clay was named Kimberlite, by the name of the place Kimberly in South Africa, where it was found first. Namely here precious crystals, which were formed at freezing of burning magma in the depth of rocks rich in carbon, are found.
For long time the diamond tubes were known only in South Africa. Here Kimberlite appeared on the surface. In all other places (Brazil, Indonesia, Australia and Ural) diamonds were found only on the river coasts and in stone placers. The water carried diamonds far away from the place were they were found before along the river channels. Only hundred years after discovering diamonds in South Africa researchers managed to find diamond tubes in the place which is least of all similar to African steppes, Yakutia.
Diamondiferous clay is mined by open method, by excavators and bulldozers. Placer deposits of diamonds in the river channels can be developed with the help of dredges. Dredges can also be used for developing gold placers.
To extract diamonds from clayey rocks, rocks are let through crushers with elastic bearings. Their rollers grind clay but cannot grind hard diamond. The ground clay is washed with water. The blocks with diamonds are heavier and fall to bottom. To separate diamonds from the rest of ground clay the latter is being dried and then being let through vibrating tables greased with vaseline. The dead rock rolls down. Diamonds stick to the tables.
Diamonds mined in the entire world during one year could be carried on one five-ton lorry. But their significance for the technique is great. American economists think that if the United States would suddenly deprive of diamonds that they receive from Africa, then their industrial power would decrease by halves.
Meanwhile precious diamond is only a carbon. From the point of view of chemist, pure coal, graphite and diamond are the same thing. The difference is only in that the atoms of carbon are ordered differently. That fact that diamond is a pure carbon and nothing else is known for one hundred and fifty years. But compounding the atoms of carbon into crystals of diamond people learned just recently. The main thing was to create the conditions in which diamonds would form in the subsoil. For this purpose the scientist had to heat the carbon to several thousand degrees of Celcius and expose to the pressure of several hundred thousand atmospheres. Several years ago scientists in our country and abroad managed to construct special devices in which such conditions are possible. The artificial diamonds are as hard as the natural ones.
Diamond jewelry comes from Greek word “adamas” that means “invincible”. In Arab the word “diamond” sounds as “almas” that means the “hardest”. It is considered as the king of semi precious stones, “the stone of kings” and was evaluated higher than all treasures. Nothing could compare with it in terms of hardness and therefore it is truly everlasting. High light refracting and wonderful play of colors indicate that cut diamonds appeared in rather unusual conditions taking place in the depth of the Universe and Earth. It seems that a saying “diamond sky” was confirmed again. American astronomer Marvin Ross from California university asserts that shining surfaces of Uranus and Neptune planets is not a frozen water consisting of ammonia and methane, but a solid layer of diamonds. Diamond flakes play with rainbow colors in these helium and hydrogen atmospheres.
First diamond jewelries were found on the territory of India. According to ancient books it took place over three thousand years BC. The bronze Greek statue with eyes of Indian diamonds and kept in Britain museum is the most ancient archeological monument. They consider that it dates back to 480 year BC.
In 1983 during building of irrigation channel in the North of India near the town of Anatnaga the workers found a statue of Rama god. It was decorated diamonds and semiprecious stones costing over million rupees. The archeologists dated back this find by XIV.
Let's repeat once again that until XV century diamond was valued lower than other precious stones. Ancient Greeks and Romans didn't know diamond. On the East it was priced lower than ruby, sapphire, lazurite, pearl and even chrysolite. This is because uncut diamond rarely looks attractive. The shine and dispersion of light become apparent only in ideally even crystals of right forms.
Diamond of the best quality is transparent, with strong shine and beautiful play of colors. People say about such a stone that it is of the first water. Nevertheless, most diamonds have a slight tint of other color: straw color, brown, off-green, bluish, reddish and black. Among them the most valuable are stones that have tints of red, blue, yellow, pink and black color.
It is well known that diamond is formed under high pressures inside the earth approximately at the depth over 80 kilometers at the temperature around 1300 degrees of Celsius. On the earth surface there are places where there are places with pressure sufficient to form diamonds. These are the places where meteorites stroke earth. Here diamond could be found not only on the earth but also on the meteorite themselves. It is supposed hat it was first found on the Noviy Ureyskiy meteorite that fell on the 10th of September 1886 in former Penza province. The scientists assume that this diamond was present in the meteorite prior to its falling, but the diamond in Arizona meteorite crater was definitely formed during the stroke against the earth.
Here is the item named "Precious newcomers from space" published in one of the newspapers on the 5th of January 1988. "Microscopic particles of diamonds aging higher than the Solar system and the Sun were found in meteorites." - say the scientists from Chicago University. - "Their chemical compound didn't change since the times of the forming of Solar System (approximately 4.5 millions of years ago). Perhaps, they are the oldest particles ever found earlier. According to Roy Louis, a physicist from Chicago, the diamonds were formed in the atmosphere of some remote star and were thrown out when this star blew up." Therefore, diamonds can be found not only under our feet and around us, but also high over our heads.
Diamond can have any color. Blue colored diamonds are quite rare and therefore more valuable. However, their brilliant play is opened only when the stone is cut in a form of cut diamond. Such diamonds are valued very high. Let's repeat blue colored diamonds are valued most of all. The crystals with slight yellowish tint are called the stones of "not of the first water" and are valued lower. Earlier the attempts to enhance the stones of "not of the first water" by covering their basaltic facets with blue film were made. After washing the stone with benzol, hot water or methyl alcohol this film could be easily removed.
Diamonds of canary yellow, greenish and brown color have undoubted refinement. Pink diamonds are less usual, while pink and lilac, ruby and red, blue colored diamonds are quite rare. Blue diamonds have as a rule, steel-blue tint. For describing semi precious stones with black specks French word "pique" (meaning "prickled all over" or "spotted by bites of insects") is used.
Since older times people valued the beauty of precious stones. Diamond, sapphire and emerald were considered as the most favorite and precious ones.
The custom to use precious stones for decorating, increasing riches and adding brilliancy to grand ceremonies was evaluated very high; lords and priests laid them up not only for confirmation of their power, but also for replenishment of treasury, ensuring military resources and for covering the government expenses. Precious stones are durable, occupy little space, and therefore from older times they were used in Palestine, where they got mainly from Tier.
